“The ECLIPSE trial reflects the growing complexity of coronary artery
disease (CAD) seen in the modern-day cardiac catheterization laboratory,
and will be the largest randomized clinical trial to date to assess the
use of adjunctive coronary atherectomy for calcific coronary artery
disease”

“The ECLIPSE trial reflects the growing complexity of coronary artery
disease (CAD) seen in the modern-day cardiac catheterization laboratory,
and will be the largest randomized clinical trial to date to assess the
use of adjunctive coronary atherectomy for calcific coronary artery
disease,” said Dr. Ajay Kirtane, director of the Cardiac Catheterization
Laboratories at NewYork-Presbyterian/Columbia University Irving Medical
Center, and co-principal investigator of the trial.

ECLIPSE will be a prospective, multi-center, randomized clinical trial
of up to 2,000 subjects performed in up to 60 sites in the United
States. Half the participants will receive orbital atherectomy prior to
DES implantation, while the other half will receive conventional
angioplasty, including specialty balloons, followed by DES implantation.
The trial will be powered to demonstrate differences in the primary
endpoints of post-procedural minimal cross-sectional area (assessed by
intravascular imaging in a subset of up to 400 patients) as well as in
the clinical outcome of target vessel failure at one year. The trial is
expected to begin recruiting in spring 2017.

Said Dr. Généreux, “Coronary calcification has been shown to increase
procedural complexity and adverse events following conventional
percutaneous coronary intervention (PCI). Using a less invasive
procedure, orbital atherectomy has the ability to significantly modify
lesion morphology, enabling successful stent delivery to help optimize
stent expansion and apposition. This valuable trial will inform
physicians regarding the most effective treatment protocols and
strategies for treating patients with calcific CAD, ultimately improving
PCI outcomes.”

CSI’s Diamondback 360® Coronary OAS is the first and only atherectomy
device approved to specifically treat severely calcified coronary
arteries. Since FDA approval on October 21, 2013, over 20,000 devices
have been used to treat patients with CAD.

Data shows that severe coronary calcium results in higher rates of major
adverse coronary events and death. It is estimated that severe calcium
is present in nearly 400,000 of U.S. coronary procedures performed
annually.

About Coronary Artery Disease (CAD)CAD is a
life-threatening condition and a leading cause of death in men and women
in the United States. CAD occurs when a fatty material called plaque
builds up on the walls of arteries that supply blood to the heart. The
plaque buildup causes the arteries to harden and narrow
(atherosclerosis), reducing blood flow. The risk of CAD increases if a
person has one or more of the following: high blood pressure, abnormal
cholesterol levels, diabetes, or family history of early heart disease.
According to the American Heart Association, 16.3 million people in the
United States have been diagnosed with CAD, the most common form of
heart disease. Heart disease claims more than 600,000 lives in the
United States each year. According to estimates, significant arterial
calcium is present in nearly 40 percent of patients undergoing a PCI.
Significant calcium contributes to poor outcomes and higher treatment
costs in coronary interventions when traditional therapies are used,
including a significantly higher occurrence of death and major adverse
cardiac events (MACE).

About Cardiovascular Systems, Inc.Cardiovascular Systems,
Inc., based in St. Paul, Minn., is a medical device company focused on
developing and commercializing innovative solutions for treating
vascular and coronary disease. The company’s Orbital Atherectomy Systems
treat calcified and fibrotic plaque in arterial vessels throughout the
leg and heart in a few minutes of treatment time, and address many of
the limitations associated with existing surgical, catheter and
pharmacological treatment alternatives. The U.S. FDA granted 510(k)
clearance for the use of the Orbital Atherectomy System in peripheral
arteries in August 2007. In October 2013, the company received FDA
approval for the use of the Orbital Atherectomy System in coronary
arteries. To date, over 260,000 of CSI’s devices have been sold to
leading institutions across the United States.

Safe HarborCertain statements in this news release are
forward-looking statements within the meaning of the Private Securities
Litigation Reform Act of 1995 and are provided under the protection of
the safe harbor for forward-looking statements provided by that Act. For
example, statements in this press release regarding the ECLIPSE clinical
trial are forward-looking statements. These statements involve risks and
uncertainties that could cause results to differ materially from those
projected, including, but not limited to, the potential for
unanticipated delays in enrolling medical centers and patients for the
ECLIPSE clinical trial, actual clinical trial results, and other factors
detailed from time to time in CSI’s SEC reports, including its most
recent annual report on Form 10-K and subsequent quarterly reports on
Form 10-Q. CSI encourages you to consider all of these risks,
uncertainties and other factors carefully in evaluating the
forward-looking statements contained in this release. As a result of
these matters, changes in facts, assumptions not being realized or other
circumstances, CSI's actual results may differ materially from the
expected results discussed in the forward-looking statements contained
in this release. The forward-looking statements made in this release are
made only as of the date of this release, and CSI undertakes no
obligation to update them to reflect subsequent events or circumstances.